Field of the Invention
The invention relates to a device for stubble treatment once a crop has been harvested, which device comprises a frame, wherein at least one knife rolling segment is adapted to be coupled to said frame through a pair of bearings and to operate substantially horizontally, said device further comprises a vibration-absorbing arrangement for each bearing, which vibration-absorbing arrangement is adapted to be mounted between a bearing and a free-end of said frame, wherein said vibration-absorbing arrangement is at least partially made of a resilient material, wherein said vibration-absorbing arrangement is adapted to isolate the frame from vibrations generated at the rolling segment and propagated to each bearing, wherein said vibration-absorbing arrangement comprises a first plate and a second plate, said first plate being adapted to be attached to the free-end of said frame and said second plate being adapted to be attached to said bearing, said plates being adapted to be fastened together, wherein one or more vibration-absorbing elements are positioned in-between said plates.
Also, the invention relates to a vibration-absorbing arrangement adapted to be mounted to a device as described above, which vibration-absorbing arrangement is adapted to be mounted to said device between a bearing and a free-end of said frame.
Description of Related Art
A device for stubble treatment can be used for many types of residual plant matters such as sunflower, maize, rape, vegetables, tobacco and cotton. In order to achieve optimal cutting/comminuting of plant material, it is important that the blades of the knife rolling segments are mounted perpendicularly to the operational direction of the device such that an entire blade strikes into the ground at once. This impact provides critical vibrations, which are transmitted to the chassis frame. Due to the high speed at which the machine is driven for efficiently cutting stubbles (e.g., 25 km/h) and consequently the high frequency at which the roller works (e.g., 30 Hz), cracks easily form in the steel structure of the frame, thus the device gets quickly damaged. If the knives are mounted differently, the shredding of plant material is significantly less effective, because said “strike” does not take place, and the roller segments simply roll over the plant material. Thus, mounting of the blades slightly obliquely to the operational direction of the device is not an efficient solution to the vibration problem. Consequently, an alternative solution is to mitigate the effect of the vibrations by reinforcing the most sensitive parts of the construction. Nevertheless, cracks will sooner or later also form in the other parts which have not been reinforced beforehand. Hence, this is not a durable and economic solution.
U.S. Pat. No. 4,407,372 illustrates a vibration-damping arrangement formed of two C-shaped springs positioned in-between the frame and each of the bearings used for mounting the shaft of a harrow. The arrangement provides graduated resilience at low impact loads by a first C-shaped spring and increased resilience at high impact loads by an additional C-shaped spring nested within the first C-shaped spring. Although damped, vibrations will still affect the frame, which will eventually experience cracks. Moreover, due to high impact loads and/or with time, the springs will get permanently deformed, thus stopping performing optimally and providing the desired damping effect.
U.S. Pat. No. 4,223,742 discloses a roller for cultivating or rolling soil. The roller consists of several hinged, interconnected frame sections, each comprising a set of rolls mounted on a common shaft rotatably attached at the free-end of downwardly extending arms. The arms are pivotally and resiliently mounted on the frame. Additionally, the arms are slightly rotatable or twistable about their longitudinal axis thanks to a rubber cushion positioned between the arm and the bearing of the shaft. However, due to vibrations, the rubber cushion may break, which results in the arm getting detached from the shaft.
Hence, there is a need in the technical field of devices for stubble treatment and related vibration-absorbing arrangements of overcoming the aforementioned drawbacks of the state-of-the-art solutions.